Coronary bypass surgery has become a common procedure, and is normally indicated for conditions requiring replacement and/or reconfiguration due to blockage of the coronary blood flow within a patient. To achieve such a bypass, grafts are surgically implanted to divert blood flow from a relatively high volume and pressure flow regime to a portion of the diseased vascular member downstream from the blockage therein. In typical bypass procedures, a section of the vascular system in a patient's body that has become impaired or inoperative through disease or other defects may be treated so as to improve flow to those portions previously being supplied with an inadequate or limited supply of blood. In order to create the graft bypass, biocompatible graft material is preferably employed, which graft material may be, for example, vascular members harvested from other portions of the patient's body or from other animals, or biocompatible artificial materials such as, for example, forms of polytetrafluoroethylene (commonly referred to as Teflon®).
While bypass procedures have been undertaken for some period of time, one particular and time consuming step is that of suturing the graft elements to respective portions of the patient's vasculature. Because of the physical properties of, in particular, artificial biocompatible graft material, suturing of such graft material is often times difficult to complete. The procedure is one which requires great dexterity, and when done at the site, is frequently in a zone with limited accessibility. Graft systems proposed to date have drawbacks with regard to ease of implantation and securement into the patient's vasculature.
An additional issue that is not satisfactorily addressed in existing bypass techniques is the inability of such techniques to effectively maintain flow and pressure from a blood flow source such as the aorta to the vascular member in which the bypass procedure is conducted. Specifically, the blood supply stream is typically in a high-pressure flow environment, while the vascular member subject to bypass flow is typically a low-pressure blood flow environment. Accordingly, the substantial pressure drop between the respective bypass blood flow locations generally results in low flow volumes to the artery or other vascular member to which bypass flow is directed. Previous attempts to provide sustained flow volumes to respective vascular members from a relatively high pressure source have been met with limited success, in that such systems proposed to date are difficult to manufacture and implement, and particularly difficult to produce positive reproducible implantation results. In particular, such prior systems fail to provide components that may be quickly and effectively implanted in the surgical process.
It is therefore a principle object of the present invention to provide a grafted network for consistently delivering sufficient blood flow volumes to respective vascular members in a bypass procedure.
It is a further object of the present invention to provide a grafted network incorporating distinct connector means for effectively channeling bypass blood flow into respective vascular members while minimizing damage to such vascular members and to such bypass blood flow.
It is a yet further object of the present invention to provide a grafted network incorporating one or more graft segments in combination with one or more distinct connector means for operably channeling bypass blood flow into respective vascular members.
It is another object of the present invention to provide a grafted network incorporating a plurality of graft segments, one or more distinct connector devices, and a flow restricting means for maintaining a desired level of blood flow pressure and volume through upstream graft segments and such connector devices into respective vascular members receiving bypass blood flow thereto.
It is a still further object of the present invention to provide a grafted network which may be expediently surgically implanted within the patient's body.